Polyolefin quaternary pyridinium salts

ABSTRACT

High molecular weight N-hydrocarbyl-substituted quaternary ammonium salts in which the hydrocarbyl group has a molecular weight of from about 350-3,000 such as a polybutene ammonium chloride are effective detergents and dispersants for gasoline and lubricating oils.

PRIOR APPLICATIONS

This application is a division of application Ser. No. 613,369, filedSept. 15, 1975 now U.S. Pat. No. 4,056,531, which in turn is a divisionof application Ser. No. 395,221, filed Sept. 7, 1973, now abandoned,which in turn is a division of application Ser. No. 255,223, filed May19, 1972, now U.S. Pat. No. 3,778,371, which in turn is acontinuation-in-part of application Ser. No. 138,758, filed Apr. 29,1971, now abandoned.

BACKGROUND

High molecular weight hydrocarbyl amines such as polybutene amines andpolyamines are known as detergents and dispersants in fuels andlubricants (Wagenaar, U.S. Pat. No. 3,275,554; Honnen et al, U.S. Pat.No. 3,438,757; Honnen et al, U.S. Pat. No. 3,565,804). These compoundsare prepared by reacting an appropriate hydrocarbyl halide with aprimary or secondary amine or polyamine under conditions such thathydrogen halide is eliminated.

Low molecular weight quaternary ammonium thiocarbamates andthiophosphates, such as dioleyl dimethylammonium dithiocarbamate oralkylbenzyl dimethyl hydroxyethylammonium O,O-dialkylphosphorodithioate,have been evaluated as antioxidants in lubricating oils (B. W. Hotten,Preprints, ACS Division of Petroleum Chemistry, Vol. 13, No. 2, pagesB-67-71, April 1968). Low molecular weight hydrocarbyl ammoniumhydroxide, such as dioleyl dimethylammonium hydroxide, a strong base,have been used in gasoline as carburetor detergents (Barusch et al, U.S.Pat. No. 3,468,640).

SUMMARY OF THE INVENTION

The present invention relates to new high molecular weight quaternaryammonium salts having an aliphatic hydrocarbon group with a molecularweight of from about 350-3000 bonded to a quaternary ammonium nitrogenatom. The anion of the salt may be any of the well-known salt anions,such as the halides (chloride, bromide, fluoride, iodide), nitrite,nitrate, carbonate, borate, alkylborates, bicarbonate, alkanoate (e.g.,acetate), phosphate, alkylphosphates, dialkylphosphates,dialkyldithiophosphates, and the like. The new compounds are useful asashless dispersants in lubricating oils and as carburetor detergents ingasoline.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of this invention is a high molecular weightquaternary ammonium salt having at least one aliphatic hydrocarbon grouphaving an average molecular weight of from about 350-3000 bonded to aquaternary ammonium nitrogen atom.

These compounds can be represented by the formula: ##STR1## in which atleast one of R₁, R₂, R₃ and R₄ is an aliphatic hydrocarbon group havinga molecular weight of about 350-3000 and the remaining R groups areindependently selected from C₁ -₂₀ alkyl, C₂ -₈ hydroxyalkyl, C₃ -₂₀alkenyl, or are joined to form a morpholine, piperidine or pyridinering, and Z is a salt anion. Preferably the high molecular weighthydrocarbon group is substantially saturated, although minor amounts ofunsaturation up to about 5 percent are acceptable. It is also preferredthat only one of R₁, R₂, R₃ and R₄ is a high molecular weightsubstantially saturated aliphatic hydrocarbon group.

The quaternary ammonium salt may be the quaternary ammonium salt of apolyamine wherein the nitrogen atom in Formula (I) represents but onequaternary ammonium nitrogen atom in said polyamine and is joinedthrough one of the R groups to one or more other quaternary ammoniumnitrogen atoms. In this case the bridging group represented by one ormore of the R groups is a divalent hydrocarbon group containing from 2to about 4 carbon atoms, such as an ethylene (--CH₂ --CH₂ --) group. Anexample is the high molecular weight aliphatic hydrocarbyl quaternaryammonium salt of N,N,N',N'-tetraalkyl ethylene diamine such asN,N,N',N'-tetraethyl ethylene diamine. Likewise, two of the R groups mayform a bridge to a single quaternary ammonium nitrogen atom such aswould be derived by quaternarizing an N,N'-dialkyl piperazine. In theseembodiments one or more of the tertiary nitrogen atoms may bequaternarized.

In an especially preferred embodiment, three of the R groups areethylene groups and form a bridge to a second nitrogen atom. Thesecompounds are quaternary ammonium salts of the compoundtriethylenediamine, a cage structure compound having the formula:##STR2##

Since this compound has two tertiary nitrogen atoms it is possible tomake both mono- and di- high molecular weight aliphatic hydrocarbonquaternary ammonium salts having the following formula: ##STR3## whereinR is a substantially saturated aliphatic hydrocarbon group having anaverage molecular weight of from 350-3000, more preferably from about800-1400, and n is 1 or 2. In practice, the salts are generally mixturesof both mono- and di- aliphatic hydrocarbon quaternary ammonium saltssuch as mono- and di- polybutene quaternary ammonium chlorides,phosphates, alkylphosphates, dialkylphosphates, borates, alkyl borates,nitrites, nitrate, carbonate, bicarbonate, alkanoate, andO,O-dialkyldithiophosphate. The preferred alkyl groups in the foregoinganions are the lower alkyl containing 1 to about 12 carbon atoms, e.g.,O,O-diisobutyldithiophosphate. Aryl groups can be substituted for alkyland are considered equivalent. The alkanoates can contain someunsaturation which can be referred to as alkenoates and, in fact, fattyacid anions, e.g., stearates, oleates, and the like, are very useful.The preferred anions are O,O-dialkyldithiophosphates and chlorides.

The quaternary ammonium salts can be made by known methods such asreacting a high molecular weight aliphatic hydrocarbon halide in whichthe hydrocarbon group has a molecular weight of from about 350-3000 withan appropriate tertiary amine at 20°-200° C., as depicted in thefollowing equation:

    R.sub.1 --Z + NR.sub.2 R.sub.3 R.sub.4 → I

in this reaction, R₁ is a high molecular weight (350-3000) aliphatichydrocarbon, and R₂, R₃ and R₄ are the same as in Formula (I) and Z is achloride, bromide, iodide, or fluoride anion as represented by Z inFormula (I). Solvents such as aliphatic hydrocarbons boiling from50°-200° C. can be used as well as aromatic hydrocarbons such asbenzene, toluene, xylene, and the like. The reaction results in theformation of a high molecular weight hydrocarbyl-substituted quaternaryammonium halide. The halide anion can be readily replaced by anotheranion by known methods such as adding a large stoichiometric excess of asalt containing the desired replacement anion to the quaternary ammoniumchloride and stirring at 50°-200° C. to displace the chloride anion. Themixture can then be filtered and water washed.

Also, as described above, the tertiary amine used in preparing thequaternary ammonium salt may be a polyamine containing tertiary aminegroups. Some representative examples of amine reactants which can bequaternized to yield compounds of this invention are:

trimethyl amine

triethyl amine

tri-n-propyl amine

dimethylethyl amine

dimethyl lauryl amine

dimethyl oleyl amine

dimethyl stearyl amine

dimethyl eicosyl amine

dimethyl octadecyl amine

N-methyl piperidine

N,n'-dimethyl piperazine

N-methyl-N'-ethyl piperazine

N-methyl morpholine

N-ethyl morpholine

N-hydroxyethyl morpholine

pyridine

triethanol amine

triisopropanol amine

methyl diethanol amine

dimethyl ethanol amine

lauryl diisopropanol amine

stearyl diethanol amine

dioleyl ethanol amine

dimethyl isobutanol amine

methyl diisooctanol amine

dimethyl propenyl amine

dimethyl butenyl amine

dimethyl octenyl amine

ethyl didodecenyl amine

dibutyl eicosenyl amine

triethylene diamine

hexamethylene tetramine

N,n,n',n'-tetramethylethylenediamine

N,n,n',n'-tetraethyl-1,3-propanediamine

methyldicyclohexyl amine

lutidine

From the above, it is apparent that the particular amine is notcritical. The critical feature of the invention is the long aliphatichydrocarbon group having an average molecular weight of from about350-3000, and preferably 800-1400, and having a quaternary ammonium saltgroup at one end. Any quaternary ammonium salt group will perform,although not all to the same degree of effectiveness, as long as thehigh molecular weight aliphatic hydrocarbyl group is attached to thequaternary ammonium nitrogen atom. Such high molecular weight aliphatichydrocarbyl groups contain from about 25 to over 200 carbon atoms.

The aliphatic hydrocarbon group can be any such group that has therequired molecular weight. For example, the group may be obtained frommineral oil sources such as the thermal cracking of paraffin wax. Thepreferred hydrocarbon groups are those derived from polymonoolefins,such as polyethylenes, polypropylenes, polybutenes, polyhexenes,polyoctenes, polydecenes, polydodecenes, and the like. Preferably, theolefin monomers are 1-olefins. The polyolefins made from C₂ -₄ olefinmonomers are preferred such as polypropylene and polybutene. Of course,polybutene, such as polyisobutylene, is especially preferred because ofthe good performance of the products obtained and the commercialavailability of the polybutenes. The quaternary salts prepared frompolyolefin halides such as polybutene chloride are referred to aspolyolefin quaternary ammonium salts, e.g., polybutene pyridiniumchloride, polybutene tri-lower alkyl ammonium chloride, or mono- or di-polybutene quaternary ammonium chloride of triethylenediamine.

The molecular weight of the aliphatic hydrocarbon group is veryimportant. The lower aliphatic hydrocarbon groups do not impart the allaround effectiveness, especially as ashless lubricating oil dispersants,that results when a high molecular weight aliphatic hydrocarbon group isbonded to the quaternary ammonium nitrogen atom. A preferred molecularweight range is from about 350-3000. Superior results are obtained whenthe hydrocarbon group has a molecular weight of from about 800-1400.

As mentioned earlier, the salt anion can be any of the common saltanions, such as chloride, bromide, fluoride, iodide, nitrite, nitrate,borate, alkylborate, carbonate, bicarbonate, alkanoate (e.g., acetate,propionate, butyrate, and the like), phosphate, alkylphosphate,dialkylphosphate, O,O-dialkyldithiophosphate, and the like. Thepreferred anions are halides. Of these, bromide and chloride areespecially preferred. The most preferred anion is chloride.

Representative examples of quaternary ammonium salts of this inventioninclude:

polybutene (m.w. 3000) trimethylammonium chloride

polybutene (m.w. 1000) triethylammonium iodide

polybutene (m.w. 350) tri-n-propylammonium bromide

polypropylene (m.w. 1500) pyridinium dioctylphosphate

C₂₅ h₅₁ tri-n-butylammonium nitrite

polybutene (m.w. 900) pyridinium-O,O-di-hexyldithiophosphate

polybutene (m.w. 1000) tri-ethanolammonium ethyl borate

polypropylene (m.w. 800) N-ethanolmorpholinium chloride

polypropylene (m.w. 900) tri-methylammonium O,O-dieicosyldithiophosphate

dipolybutene (m.w. 900) triethylenediammonium dichloride

dipolypropylene (m.w. 1100) triethylenediammonium dichloride

N-polybutene (m.w. 850) triethylenediamine chloride

N-polybutene (m.w. 1200) triethylenediamine dioctyl dithiophosphate

Further examples will be apparent to any chemist by mere inspection ofthe previous list of tertiary amines which may be quaternized by a highmolecular weight substantially saturated aliphatic hydrocarbon halide toproduce the initial quaternary ammonium halide which may, if desired, beconverted to various such salts by exchanging anions by known methods.

The quaternary ammonium dispersants and detergents of this invention aremore easily made compared to the methods required to prepare similarprior art additives. For example, the preparation of the priorhydrocarbyl amine detergents requires the reaction of an appropriatehydrocarbyl halide with a primary or secondary amine for long periods oftime at elevated temperatures. The conditions must be such that thehydrogen halide is eliminated according to the reaction: ##STR4## Thehydrogen halide formed must be removed or the product could causecorrosion. No such restrictions are placed on the preparation of thepresent additives. The high molecular weight hydrocarbyl halide ismerely mixed with the appropriate tertiary amine and warmed to form thequaternary ammonium salt. Hydrogen halide is not expelled from thereaction.

The high molecular weight aliphatic hydrocarbyl halides used toquaternarize the amine can be made by known methods, such as thewell-known halogenation of aliphatic hydrocarbons. The high molecularweight aliphatic hydrocarbon can be obtained from any source, such asthe thermal cracking of paraffin wax or, preferably, from thepolymerization of olefins. The polyolefin starting material ispreferred. The olefins used to prepare the starting material can be anyolefin hydrocarbon, such as those containing from 2 to about 32 carbonatoms. The higher olefins such as those containing from 12-32 carbonatoms need not be polymerized to a great extent, but need only bedimerized, trimerized or tetramerized to obtain the required molecularweight. Such olefin polymers are described more fully later, since theycan also be used together with compounds of this invention as gasolineadditives. Thus, in one embodiment of the invention the polyolefinstarting material is a mixture of oligomerized C₁₂₋₃₂ olefins in whichthe oligomer has a molecular weight of from about 350-1500.

The preferred polyolefin starting material is the poly-C₂₋₄ olefins,especially the poly-C₃₋₄ olefins. Any of the polyolefins are readilyhalogenated by merely passing a halogen into the material at moderatetemperatures.

This halogenation can be carried out under relatively mild conditions.The temperature at which the reaction can be carried out may be variedover a wide range. Thus, the halogenation can be accomplished attemperatures ranging from 50° to 150° C. In general, the halogenation iseffected by dissolving the polyolefin in a solvent such as benzene,tetrahydrofuran, and the like, and treating the solution with thehalogen, for example, chlorine gas, or a halogenating reagent, such asN-bromo succinimide. The polyolefin halide is also obtained byhalogenating polyolefin without any solvent being present. The physicalcharacteristics of the polyolefin, for example, its viscosity, will helpdetermine whether a solvent should be used. The halogenation proceedswhether a solvent is used or not. The reaction is generally complete in15 to 120 minutes. The following examples will illustrate typicalhalogenation procedures. All parts by weight unless otherwise specified.

EXAMPLE 1

A solution of 301 parts of Polybutene-24 (Chevron Chemical Companydesignation for polyisobutylene of molecular weight about 950) in 120parts of benzene was placed in a vessel equipped with thermometer,stirrer, gas inlet tube and condenser. The solution was heated to about73° C. and 22.7 parts of chlorine gas was bubbled through over a periodof about one hour.

The reaction vessel was then flushed with nitrogen gas for one hour. Thesolution was filtered and the solvent was removed by vacuumdistillation. The yield was 312 parts of polyisobutyl chloride. Theproduct was a cloudy orange-colored viscous liquid, which on analysiswas found to contain 3.55 percent chlorine. Infrared analysis showedthat the compound was unsaturated.

EXAMPLE 2

A reaction vessel fitted with a thermometer, stirrer and condenser wascharged with 94.1 parts of Polybutene-24 (defined in Example 1), 17.8parts of N-bromo succinimide and 200 parts of benzene. The mixture wasrefluxed for about 30 minutes. The mixture was then cooled and thesolution was filtered. The solvent was stripped and the residue was thenredissolved in hexane. This solution was filtered and the solvent wasremoved by vacuum distillation. A 99 percent yield of the polyisobutylbromide was obtained as a dark brown viscous liquid. The bromine contentof this product was 7.9 percent.

The following example illustrates the halogenation of a polyolefinfollowed by quaternarization of the resultant hydrocarbyl halide.

EXAMPLE 3

In a reaction vessel was placed 180 parts of polybutene (averagemolecular weight 800) and 100 parts of benzene. Chlorine was passed intothe solution at 80°-90° C. for one hour. The system was then purged ofchlorine by passing nitrogen through it for an hour. Following this, 40parts of pyridine was added and the mixture stirred at 120°-130° C. for3 hours. The resultant product was washed with water and then heatedunder vacuum to remove solvent. It was diluted with an SAE-10 neutralmineral oil to form a 50 weight percent active concentrate of polybutenepyridinium chloride in which the polybutene group bonded to thequaternarized pyridinium nitrogen atom had an average molecular weightof 800. Polybutene and polybutenyl as well as polypropylene andpolypropenyl when referring to aliphatic hydrocarbon groups are usedinterchangeably herein.

The following examples illustrate the replacement of the chloride anionwith various other anions.

EXAMPLE 4

In a reaction vessel was placed 25 parts of the polybutene pyridiniumchloride from Example 3 and 13 parts of O,O-di-C₂₀₋₃₀ alkyl zincphosphorodithioate. To this mixture was added about 25 parts ofpetroleum ether and the mixture was stirred at reflux for 30 minutes.The mixture was cooled and filtered to remove the zinc chlorideprecipitate and the filtrate washed with water. It was then heated undervacuum to distill out the petroleum ether. The product was an oildilutedconcentrate containing polybutene pyridinium O,O-diC₂₀₋₃₀ alkylphosphorodithioate.

EXAMPLE 5

In a reaction vessel was placed 25 parts of the polybutene pyridiniumchloride from Example 3, 25 parts of petroleum ether and 5 parts ofsodium nitrite dissolved in a water-methanol mixture. The mixture washeated and stirred for 30 minutes. The small aqueous phase present wasthen removed and the product heated under vacuum to distill out solvent.The remaining product was filtered, yielding a mixture containingpolybutene pyridinium nitrite.

EXAMPLE 6

In a reaction vessel was placed 25 parts of the polybutene pyridiniumchloride from Example 3 and 6.25 parts of sodium dibutyldithiocarbamate. Twenty parts of petroleum ether were added and themixture stirred at reflux for 30 minutes. The product was filtered andthe solvent distilled off under vacuum, resulting in a concentratecontaining polybutene pyridinium dibutyl dithiocarbamate.

EXAMPLE 7

In a vessel was placed 25 parts of the polybutene pyridinium chloridefrom Example 3 and 5 parts of didecyl hydrogen phosphate. The mixturewas stirred and heated under vacuum for one hour, during which periodhydrogen chloride evolved. The resultant mixture was an oil concentratecontaining polybutene pyridinium didecylphosphate.

EXAMPLE 8

In a closed reaction vessel place 1000 parts of polypropylene bromide(made by brominating polypropylene having an average molecular weight of950). Add 500 parts of toluene and 90 parts of trimethyl amine. Stir andheat the mixture to reflux. Reflux for an hour and then cool and washtwice with 500 part portions of water. Heat to about 150° C. undervacuum (approximately 10 mm Hg) to distill out the toluene solvent. Theproduct is a polypropenyl trimethyl ammonium bromide in which thepolypropenyl group has an average molecular weight of 950.

Other amines can be used in the above example with good results. Thefollowing table lists such other amines and the corresponding productwhich forms.

    ______________________________________                                        AMINE         QUATERNARY AMMONIUM SALT                                        ______________________________________                                        triethyl amine                                                                              polypropenyl triethyl ammonium                                                bromide                                                         lauryl dimethyl amine                                                                       polypropenyl lauryl dimethyl                                                  ammonium bromide                                                eicosyl dimethyl amine                                                                      polypropenyl eicosyl dimethyl                                                 ammonium bromide                                                dioleyl methyl amine                                                                        polypropenyl dioleyl methyl                                                   ammonium bromide                                                distearyl ethyl amine                                                                       polypropenyl distearyl ethyl                                                  ammonium bromide                                                dilauryl methyl amine                                                                       polypropenyl dilauryl methyl                                                  ammonium bromide                                                N-methyl piperidine                                                                         polypropenyl methyl pyridinium                                                bromide                                                         N-methyl morpholine                                                                         polypropenyl methyl morpholinium                                              bromide                                                         triethanol amine                                                                            polypropenyl tri(2-hydroxy-                                                   ethyl)ammonium bromide                                          diethanol ethyl amine                                                                       polypropenyl di(2-hydroxy-                                                    ethyl) ethyl ammonium bromide                                   N,N,N',N'-tetramethyl                                                                       dipolypropenyl tetramethyl                                      ethylene diamine                                                                            ethylene diammonium bromide                                     nitrilotriacetonitrile                                                                      polypropenyl triaceto nitrile                                                 ammonium bromide                                                ______________________________________                                    

EXAMPLE 9

In this example the starting hydrocarbon is an olefin oligomer preparedby polymerizing a mixture of C₁₂₋₃₂ 1-olefins using an aluminum chloridecatalyst to obtain an oligomer having an average molecular weight of550. The preparation of this oligomer will be described later.

In a reaction vessel place 550 parts of the above oligomer and heat to80°-90° C. Pass chlorine into the liquid until one mole part hasreacted. Following this, pass nitrogen through the liquid for 10 minutesto remove residual chlorine. Then add 100 parts of pyridine and 250parts of toluene. Heat the mixture to 130° C. and stir for an hour. Cooland wash with water and then distill out the toluene under vacuum. Add630 parts of an SAE-10 neutral mineral oil to obtain a 50 weight percentactive concentrate a poly-C₁₂₋₃₂ 1-olefin pyridinium chloride.

Other hydrocarbons having an average molecular weight of from about350-3000 can be used in the above example in place of the poly-C₁₂₋₃₂1-olefin. These can be obtained directly from mineral oil or can bethermally cracked paraffin wax. Likewise, polymers of lower 1-olefinssuch as polypropylene or polyisobutylene can be used with excellentresults.

EXAMPLE 10

In a reaction vessel was placed 200 grams of polybutene chloride (frompolybutene having an average molecular weight of 950) and 30 grams ofdimethyl acetamide. The mixture was heated to 90° C. and trimethylaminewas bubbled through it for 1.75 hours. The resultant product wasdistilled under vacuum to remove volatiles and the residual liquiddiluted with 100 grams of light mineral oil, giving a detergentconcentrate of polybutene trimethyl ammonium chloride.

EXAMPLE 11

In a reaction vessel was placed 20 grams of the polybutenetrimethylammonium chloride from Example 10 and 2 grams of hexyleneglycolacid borate. The mixture was stirred and heated on a steam bath for onehour and then distilled under vacuum, yielding a polybutenetrimethylammonium hexyleneglycol borate.

EXAMPLE 12

In a reaction vessel as used in Example 1 was placed 200 grams ofpolybutene chloride prepared as in Example 1. To this was added 13.4grams of triethylenediamine and 40 grams of methylethyl ketone solvent.The mixture was stirred at 130°-137° C. for one hour and then dilutedwith 75 grams of light mineral oil and 30 grams of n-dodecanol. Theconcentrate was diluted with an equal volume of hexane and washed firstwith lime water and then with water. It was then filtered and thevolatiles distilled out under vacuum, yielding 303 parts of a dispersantconcentrate (approximately 67 percent active).

EXAMPLE 13

In a reaction vessel as used in Example 1 was placed 50 grams ofpolybutene chloride (from Example 1), 7 parts of hexamethylenetetramineand 15 parts of N,N-dimethyl acetamide solvent. The mixture was stirredfor 75 minutes at 150°-155° C. to form a polybutenyl quaternary ammoniumchloride of hexamethylenetetramine.

EXAMPLE 14

In a reaction vessel was placed 100 grams of polybutene chloride (fromExample 1) and 200 grams of pyridine. The mixture was stirred at 188° C.for 3.5 hours, following which unreacted pyridine was distilled out atreduced pressure. The product was diluted with an equal volume of hexaneand filtered. The hexane was distilled out and the product diluted with54 grams of light mineral oil to give 163 grams of 67 percent activepolybutenyl pyridinium chloride.

The alkyl hydrogen phosphate salt was prepared by heating a mixture ofn-decanol and dodecanol and P₂ O₅ for 2 hours at 90°-95° C. It wasdiluted with petroleum ether and water washed. It was converted to itssodium salt by adding 53 grams of sodium hydroxide to bring the pH to8-9.

The above polybutenyl pyridinium chloride was converted to an alkylphosphate salt by mixing 50 grams of the chloride salt with 5 grams ofthe above sodium alkyl phosphate, diluting the mixture with hexane andstirring for 1/2 hours at reflux. The product was washed with water toremove sodium chloride and the hexane distilled out under vacuum toleave a polybutenyl pyridinium alkyl phosphate.

EXAMPLE 15

In a reaction vessel was placed 634 grams of polybutene chloride(average molecular weight 950) and 500 ml of chlorobenzene. The mixturewas heated to 130° C. and chlorine injected for one hour and 35 minutes.Solvent was distilled out, leaving a polybutene chloride.

In a second reaction vessel was placed 100 grams of the above polybutenechloride, 6.7 grams of triethylenediamine and 50 grams of methylethylketone. The mixture was stirred 1 hour at 90°-93° C., diluted withhexane, water washed and filtered. It was then diluted with 50 grams oflight mineral oil and distilled under vacuum to remove volatilematerials.

EXAMPLE 16

One-half of the product prepared in Example 15 was added to a saturatedsolution of sodium nitrite in dimethylformamide. The mixture was heatedto reflux and stirred 30 minutes following which it was washed withwater and distilled to remove volatiles, resulting in a residuecontaining polybutenyl quaternary ammonium nitrite salt oftriethylenediamine.

The quaternary ammonium salts of this invention are excellentdispersants for lubricating oil including both synthetic (e.g., esterbased oils) and mineral lubricating oils. Tests were carried out todemonstrate their effectiveness.

SLUDGE DISPERSANCY TEST

In this test a test blend is prepared using 7 grams of a typical enginesludge material, 2 grams of water, one gram of test additive andsufficient neutral mineral oil to make a 100 gram blend. This materialis emulsified in a blender for 20 minutes and then centrifuged for 2.5hours. Following this, the percent light transmittance of the oil justbeneath the surface is measured photoelectrically. The better thedispersant, the more of the sludge that will remain suspended followingthe centrifuging, and hence the lower the percent light transmittancethat will be measured. The light transmittance of the test oil iscompared to the transmittance of the base oil subject to the sameconditions but without any dispersant. This shows the degree ofdispersant effectiveness. The following results were obtained.

    ______________________________________                                                                  Percent Light                                       Additive of                                                                              Conc. (wt. %)  Transmittance                                       ______________________________________                                        None       --             59                                                  Example 3  1              1                                                   Example 4  1              2                                                   Example 5  1              11                                                  Example 6  1              26                                                  Example 7  1              1                                                   Example 13  0.5           4                                                   Example 13  1.0           1                                                   Example 12  0.5           3,4,7,9,14                                          ______________________________________                                    

As the above tests show, the dispersants of the present inventionretained the sludge in a dispersed form even after 2.5 hours ofcentrifuging to such a degree that as little as 1 percent of the lightwould transmit through the oil compared to 59 percent of the light whichwas transmitted through the non-dipsersant oil.

Additives of this invention have been subjected to engine tests. Thetests employed were standard L-43 single cylinder tests in which anengine is operated under controlled conditions and the amount of sludgeand varnish accumulated on various engine components is visually ratedperiodically on a scale from 0-10 (10 being perfectly clean). The testcriteria is the number of hours until the average sludge and varnishrating drops to 9. The test oil contained 0.08 percent zinc as acommercial zinc dialkyldithiophosphate. The results obtained were asfollows:

    ______________________________________                                                   Conc.    Hours                                                     Additive     %         Sludge    Varnish                                      ______________________________________                                        none         --        39        48                                           Example 14   0.5       43        60+                                          Example 12   0.5       52        60+                                          commercial disp.*                                                                          0.5       55        60+                                          ______________________________________                                         *A commercial high molecular weight alkenyl succinimide of                    polyethylenepolyamine, e.g., tetraethylenepentamine.                     

The additives of this invention are useful dispersants in both mineraland synthetic lubricating oils. Examples of mineral lubricating oilsinclude those refined from any crude oil such as Pennsylvania,midcontinent, Gulfcoast, Calif., and the like. The synthetic lubricantsinclude both the hydrocarbon type and the other various types ofsynthetic lubricants. Hydrocarbon synthetic lubricants are generallypolyolefin oligomers or alkylated aromatics. Examples are polybuteneoligomers, styrene isobutylene copolymers, β-decene trimers, tetramers,pentamers, and mixtures thereof, mixtures of alkylated benzenes fromC₁₂₋₂₆ olefins and having an average molecular weight of 450, and thelike. The polyolefin oligomers are readily prepared from the appropriateolefin by standard oligomerization catalysts such as aluminum chloride,boron trifluoride, diethyl aluminum chloride, ethyl aluminumsesquichloride, combinations of aluminum alkyls and metal salts such asdiethyl aluminum chloride-titanium tetrachloride, ethyl aluminumsesquichloride-butyl vanadates, triethyl aluminumzirconium iodides, andthe like.

The alkylated aromatics are made by alkylating aromatics such asbenzene, toluene, naphthalenes, and the like, with olefin mixturespreferably containing C₁₂₋₃₂ olefins. Catalysts such as AlCl₃ and BF₃are effective and the average molecular weight of the product should befrom about 300 to 600.

The additives are very effective in synthetic ester type lubricantsincluding monoesters, diesters, complex esters, and the like. Someexamples are C₅₋₁₀ aliphatic monocarboxylic acid esters oftrimethylolpropane, n-hexanoic ester of pentaerythritol, C₅₋₉ aliphaticmonocarboxylic esters of equal mole mixtures of trimethylolpropane andpentaerythritol, adipic acid diesters of C₇₋₁₂ monohydric alkanols,complex esters formed by esterifying mixtures of polyols, dicarboxylicacids and monocarboxylic acids. For example, a useful complex ester isformed by condensing adipic acid, ethyleneglycol and a C₅₋₁₀ mixture ofaliphatic monocarboxylic acids. Another complex ester is formed fromtrimethylolpropane, adipic acid and C₁₀₋₁₂ fatty alcohol mixtures. Inessence, the complex esters are condensation products of polycarboxylicacids, polyols, and either monocarboxylic acids or monohydric alkanols,or both.

Other synthetic lubricants include the polyalkyl siloxanes, polyalkylsilicates, alkyl silicones, polyfluoro hydrocarbons, polyaryl ethers,polyalkoxy aryls, polyglycols, and the like.

The lubricant compositions are prepared by merely blending a dispersantamount of the additive with the oil. An effective amount is usually fromabout 0.1 to 5 weight percent, although more or less can be beneficiallyemployed.

The lubricant compositions can include the other ingredients normallyadded to formulated lubricants. For example, mineral oil and synthetichydrocarbon oil lubricants generally include zincdialkyldithiophosphates, calcium alkyl sulfonates, overbased calciumsulfonates containing colloidal calcium carbonate, calcium phenates,antioxidants such as 4,4'-methylenebis-(2,6-di-tert-butylphenol),2,6-di-tert-butyl-α-dimethyl amino-p-cresol, phenylene diamines, bariumphosphonates, polyalkyl methacrylate V.I. improvers, and the like.Synthetic ester formulations may include phosphate ester wear inhibitorssuch as tricresyl phosphate, phenyl dicresyl phosphate, and the like,antioxidants such as phenyl-β-naphthyl amine, phenylene diamines,phenothiazines, and the like, metal deactivators, silicone antifoamagents, and the like.

The following examples illustrate the preparation of some preferredlubricant compositions of this invention.

EXAMPLE 17

In a blending vessel is placed 10,000 parts of solventrefined,midcontinent, neutral mineral oil (100 SUS). To this is added 100 partsof zinc diisobutyl dithiophosphate, 150 parts of overbased calciumalkaryl sulfonate (300 base number), 200 parts of polylaurylmethacrylateV.I. improver, and 50 parts of4,4'-methylenebis-(2,6-di-tert-butylphenol). Following this, 35 parts ofpolyisobutene pyridinium chloride of Example 3 is added. The mixture iswarmed to 50° C. and stirred until homogeneous, giving a lubricant ofgood stability and excellent dispersant properties suitable for use inautomotive engines.

EXAMPLE 18

In a blending vessel is placed 10,000 parts of a hindered esterlubricant made by esterifying trimethylolpropane with a mixture of C₆and C₈ n-aliphatic carboxylic acids. Following this, there is added 100parts of phenyl-α-naphthyl amine, 100 parts of dioctyldiphenyl amine, 10parts of 1-salicylalaminoguanadine, 300 parts of tricresyl phosphate,and .05 part of dimethyl silicone. Then, 300 parts of the polypropenyltrimethyl ammonium bromide of Example 8 is added. The mixture is warmedto 50° C. and stirred for 15 minutes. It is then filtered to give asynthetic ester lubricant suitable for use in turbines and turbojetengines.

The manner in which the additive is blendedwith the other lubricantsmentioned is apparent from the foregoing examples.

The additives of this invention are also useful as detergents in liquidhydrocarbon fuels including distillate fuels, such as diesel fuel andliquid hydrocarbon fuels of the gasoline boiling range. Liquidhydrocarbon fuels of the gasoline boiling range are mixtures ofhydrocarbons having a boiling range of from about 80° to about 430° F.(ASTM D-86). Of course, these mixtures can contain individualconstituents boiling above or below these figures. These hydrocarbonmixtures contain aromatic hydrocarbons, saturated hydrocarbons andolefinic hydrocarbons. The bulk of the hydrocarbon mixture is obtainedby refining crude petroleum by either straight distillation or throughthe use of one of the many known refining processes, such as thermalcracking, catalytic cracking, catalytic hydroforming, catalyticreforming, and the like. Generally, the final gasoline is a blend ofstocks obtained from several refinery processes. The final blend mayalso contain hydrocarbons made by other procedures such as alkylate madeby the reaction of C₄ olefins and butanes using an acid catalyst, suchas sulfuric acid or hydrofluoric acid.

Preferred gasolines are those having a Research Octane Number of atleast 85. A more preferred Research Octane Number is 90 or greater. Itis also preferred to blend the gasoline such that it has a content ofaromatic hydrocarbons ranging from 10 to about 60 volume percent, anolefinic hydrocarbon content ranging from 0 to about 30 volume percent,and a saturate hydrocarbon content ranging from about 40 to 80 volumepercent, based on the whole gasoline.

The amount of the detergent added to the fuel should be at leastsufficient to exert some detergent action in the fuel induction system.In other words, it should be a detergent amount. Detergent action isgenerally attained when the fuel contains from about 10-2000 ppm (partsper million) of the new detergent, and more preferably, when it containsfrom about 20-1000 ppm.

The gasoline may contain any of the other additives normally employed togive fuels of improved quality, such as tetraalkyllead antiknocksincluding tetramethyllead, tetraethyllead, mixed tetraethyltetramethyllead, and the like. They may also contain antiknock quantities of otheragents such as cyclopentadienyl nickel nitrosyl, methylcyclopentadienylmanganese tricarbonyl and N-methyl aniline, and the like. Antiknockpromoters such as tert-butyl acetate may be included. Halohydrocarbonscavengers such as ethylene dichloride, ethylene dibromide and dibromobutane may be added. Phosphorus-containing additives such as tricresylphosphate, methyl diphenyl phosphate, diphenyl methyl phosphate,trimethyl phosphate, and tris(β-chloropropyl)phosphate may be present.Antioxidants such as 2,6-di-tert-butylphenol,2,6-di-tert-butyl-p-cresol, phenylenediamines such asN-isopropylphenylenediamine, and the like, may be present. Likewise, thegasoline can contain dyes, metal deactivators, or any of the additivesrecognized to serve some useful purpose in improving the gasolinequality.

A preferred embodiment of the invention is a liquid hydrocarbon fuel ofthe gasoline boiling range containing a detergent amount of the newdetergent of this invention and from about 0.25 to 4 grams per gallon oflead as tetraethyllead or tetramethyllead. A still further embodiment ofthe invention is a liquid hydrocarbon fuel of the gasoline boiling rangecontaining a detergent amount of the new detergent of this invention andfrom about 0.005 to 3, more preferably 0.005 to 0.5, grams of manganeseper gallon as methylcyclopentadienyl manganese tricarbonyl.

A highly preferred embodiment of this invention is a liquid hydrocarbonfuel of the gasoline boiling range as previously described containing inaddition to the detergent additive a small amount of a mineral oil. Thisembodiment is particularly advantageous in promoting the cleaning ofintake valves and stems in spark ignited internal combustion engines.The amount of oil added can be any amount from about 0.05 to about 0.5volume percent, based on the final gasoline. Although the oil adjuvantcan be any of the well-known mineral oils, including those obtained fromPennsylvania, midcontinent, Gulf-coast, or California crudes, the morepreferred are the naphthenic mineral oils. The viscosity of the mineraloil can vary from about 100 to 2000 SUS at 100° F.

In another preferred embodiment a synthetic olefin oligomer is used inplace of or together with the mineral oil adjuvant. These oligomers areprepared by the polymerization of one or more aliphatic monoolefinichydrocarbons containing from 2 up to about 32 carbon atoms, such asethylene, propylene, butene, decene-1, eicosene-1, triacontene-1, andthe like. These result in such adjuvants as polyethylene, polypropylene,ethylene-propylene copolymer, polybutene, styrene-butadiene copolymer,α-decene trimer, α-decene tetramer and mixtures of the proper averagemolecular weight.

The gasoline detergent additives of this invention can be added directlyto gasoline or they can be added in the form of a concentrate. Thus,another embodiment of the invention is a gasoline detergent concentratecontaining an additive amount of a detergent of this invention and adiluent. The amount of detergent in the concentrate can vary from about10-90 weight percent. A preferred concentration is from about 35-75weight percent. The diluent serves to maintain the concentrate in aliquid form, making it easy to handle and to meter into gasolineblending systems. Preferred diluents are hydrocarbons including bothaliphatic and aromatic hydrocarbons such as hexane, heptane, octane,petroleum ether, kerosene, benzene, toluene, xylene, and the like,including mixtures thereof. A more preferred diluent is a higher boilinghydrocarbon such as a mineral oil or polyolefin oligomer. The advantageof using these higher boiling hydrocarbon diluents is that these higherboiling hydrocarbons also serve as the previously-described mineral oilor polyolefin adjuvants. Thus, a preferred concentrate contains fromabout 10-90 weight percent, preferably 35-75 weight percent, of thedetergent in a mineral oil or polyolefin oligomer. When this concentrateis added to gasoline a fuel is provided which will maintain the entireinduction system in a high degree of cleanliness.

Especially good results have been obtained when the hydrocarbon diluentemployed in the concentrate is one of the previously-describedpolyolefin oligomers made by polymerizing an olefin or mixture ofolefinic hydrocarbons containing about 12 or more carbon atoms,preferably from 12-32 carbon atoms; to produce a liquid olefin polymerhaving an average molecular weight of about 300-1500.

The detergent concentrate can contain other additives normally used withgasoline, forming an additive "package". For example, the concentratecan contain gasoline antioxidants such as 2,6-di-tert-butylphenol,mixtures of butylated phenol containing about 75 percent of2,6-di-tert-butylphenol, 15 percent o-tert-butylphenol,N-isopropylphenylenediamine; phosphorus additives such as tricresylphosphate, trimethylphosphate, phenyldimethylphosphate,dimethylphenylphosphate, tris(β-chloropropyl)phosphate, and the like;antiknock promoters such as tert-butyl acetate; de-icers such asmethanol, isopropanol, n-butanol, isobutanol; tetraalkyllead antiknockssuch as tetraethyllead, tetramethyllead, redistributedtetraethyltetramethyllead, and the like; scavengers such as ethylenedichloride, ethylene dibromide, dibromobutanes, and the like; otherantiknock agents such as methyl cyclopentadienyl manganese tricarbonyl,ferrocene, methyl ferrocene, cyclopentadienyl nickel nitrosyl,N-methylaniline, and the like; metal deactivators such asN,N'-disalicylidene-1,2-diaminopropane, dyes; corrosion inhibitors, andthe like.

The concentrates of this invention are readily prepared by merelyblending the ingredients until a homogeneous solution is obtained. Thefollowing examples illustrate the preparation of some typicalconcentrates.

EXAMPLE 19

To a blending vessel is added 1000 parts of the detergent product fromExample 3 and 1000 parts of a naphthenic mineral oil. The mixture iswarmed and stirred until homogeneous, forming an additive concentrateuseful for improving the detergent properties of gasoline.

EXAMPLE 20

To a blending vessel is added 1000 parts of the detergent additive fromExample 5 and 1500 parts of the olefin oligomer. Then, 20 parts of amixture of butylated phenols containing about 75 percent2,6-di-tert-butylphenol are added. This mixture is stirred, forming adetergent package which also imparts antioxidant protection when addedto gasoline.

The amounts of each ingredient in the foregoing compositions can bevaried within wide limits to provide the optimum degree of eachproperty.

Gasoline compositions of this invention can be prepared by merely addingthe detergent in the proper amount to the gasoline base stock andstirring until dissolved. Likewise, the detergent can be injected intothe gasoline stream in an in-line blending system either alone or incombination with other additives such as tetraalkyllead antiknocks.Similarly, the additive concentrate can be added to gasoline, furnishingnot only the detergent but also the adjuvant (mineral oil or olefinoligomer). If desired, the detergent and adjuvant can be separatelyadded to the base gasoline.

The following examples serve to illustrate the manner in which gasolinecompositions of this invention are made. In these examples the gasolinebase stocks have the following composition and properties.

    ______________________________________                                                Boiling                                                                       Range (° F.)                                                                    Composition                                                                        End  %       %     %                                    Fuel  RON     Initial Point                                                                              Aromatics                                                                             Olefins                                                                             Saturates                            ______________________________________                                        H     91      91      390  40      1.5   58.5                                 I     86      100     400  35      2     63                                   J     87      95      410  36.5    2.5   61                                   K     95      89      395  49.5    2.5   48                                   L     97      105     415  54      1.5   44.5                                 M     90      96      389  39      3     58                                   N     94      87      395  51      0.5   48.5                                 ______________________________________                                    

EXAMPLE 21

In a blending vessel is placed 10,000 gallons of Gasoline H, 25 poundsof the detergent of Example 3, 100 pounds of the polyisobutylene (mol.wt. 1000), 96.5 pounds of tetraethyllead as a commercial antiknock fluidcontaining one theory of ethylene dichloride and 0.5 theory of ethylenedibromide, and 15.5 pounds of tricresylphosphate. The mixture is stirreduntil thoroughly mixed. The resultant gasoline is a premium gradegasoline with good detergent properties.

EXAMPLE 22

In a blending vessel is placed 10,000 gallons of Gasoline L, 2.5 poundsof detergent of Example 5, and 50 pounds of a neutral mineral oil(viscosity 100 SUS at 100° F.). The mixture is stirred, resulting in anunleaded gasoline having good detergent properties.

EXAMPLES 23 - 32

The above Examples 21 and 22 are repeated using each of Gasolines I, J,K, M and N.

EXAMPLE 33

To a blending vessel is added 10,000 gallons of Gasoline I, 100 poundsof the additive package of Example 20, 84 pounds of tetraethyllead as acommercial antiknock fluid, and 4.8 pounds of trimethylphosphate. Themixture is stirred, giving a high quality gasoline of good detergentproperties.

Tests were carried out to demonstrate the carburetor detergentproperties of the present additive. In these, the additive was added togasoline which was used to operate a six cylinder L-head engine for 2hours using exhaust recycle to the carburetor. The carburetor is cleanat the start of the test and the criteria of effectiveness is thecarburetor deposit weight formed. The results obtained were as follows:

    ______________________________________                                                                 Carburetor                                           Additive       Conc.     Deposit Wt. (mg)                                     ______________________________________                                        none           --        3.2*                                                 Example 10     20 ppm**  1.5, 1.8                                             Example 11     20 ppm    1.4, 1.5                                             Example 14     20 ppm    1.3                                                  ______________________________________                                         * Average value                                                               ** Parts per million                                                     

As the test results show, the additives of this invention reducecarburetor deposits to about one-half that normally obtained.

I claim:
 1. A high molecular weight quaternary pyridinium salt effectiveas a detergent in distillate fuels and as a dispersant in lubricatingoils, said pyridinium salt being soluble in said fuels and lubricatingoils, said pyridinium salt having a substantially saturated poly-C₂₋₄olefin hydrocarbon group having an average molecular weight of fromabout 800 to 1,400 bonded to the pyridinium nitrogen atom, the anions ofsaid pyridinium salt being selected from the group consisting ofhalides, phosphate, C₁₋₁₂ alkylphosphate, di-C₁₋₁₂ alkyl phosphate,borate, C₁₋₁₂ alkylborate, nitrite, nitrate, carbonate, bicarbonate,C₁₋₁₂ alkanoate, and di-C₁₋₁₂ alkyl dithiocarbamate, and O,O-di-C₁₋₁₂alkyl dithiophosphate.
 2. A quaternary pyridinium salt of claim 1wherein said poly-C₂₋₄ olefin hydrocarbon group is a polyisobutylenegroup.
 3. A quaternary pyridinium salt of claim 2 wherein said saltanion is chloride.
 4. A quaternary pyridinium salt of claim 2 whereinsaid salt anion is O,O-dialkyldithiophosphate.
 5. A quaternarypyridinium salt of claim 2 wherein said salt anion is nitrite.
 6. Aquaternary pyridinium salt of claim 2 wherein said salt anion is adi-C₁₋₁₂ alkyl dithiocarbamate.
 7. A quaternary pyridinium salt of claim6 wherein said salt anion is a di-butyl dithiocarbamate.
 8. A quaternarypyridinium salt of claim 2 wherein said salt anion is di-C₁₋₁₂ alkylphosphate.
 9. A quaternary pyridinium salt of claim 8 wherein said saltanion is di-decyl phosphate.